The present invention relates generally to automotive repair and more particularly to the repair of radiators and specifically the repair of broken mouth assemblies of radiators.
Automotive engines are provided with radiators through which the engine coolant is pumped to cool it after it has absorbed heat from the engine. In most cases, these radiators comprise an array of cooling fins through which coolant tubes extend and are located at the front of a vehicle. Thus, wind passing through the cooling fins of the radiator efficiently cools the liquid coolant as it passes through the coolant tubes. In addition, radiators are also provided with a reservoir for holding engine coolant. The reservoir, in turn, is provided with a mouth assembly through which coolant can be added to the system. In general, the mouth assembly of a radiator has a generally tubular configuration with an open top end through which coolant can be added to the reservoir. The open top end is configured to receive a sealing cap to close the mouth and seal off the radiator reservoir. The radiator cap is provided with a spring biased gasket that can be overcome when pressure within the reservoir rises above a predetermined level to allow excess pressure and coolant to escape from the reservoir. The spring biased gasket also allows excess water to escape from the reservoir as the water is heated and expanded in volume during normal operation of the engine.
In recent years, radiator mouth assemblies in vehicles have been provided with overflow tube nipples that project outwardly from the tubular body of the mouth assembly. These overflow tube nipples, in turn, are coupled to one end of a flexible overflow hose, which communicates at its other end with an ancillary reservoir within the engine compartment. When coolant escapes from the radiator reservoir, it is delivered through the overflow tube nipple and the flexible overflow hose into the ancillary reservoir. In this way, the coolant is not lost from the system and can be drawn back into the radiator as needed.
In the last few years, radiator reservoirs and their mouth assemblies have been formed of molded plastic rather than copper or other metals that were previously used. The molded plastic is more economical than metal and does not have to be soldered at critical joints as with metal. Accordingly, the molded plastic reservoirs are more reliable than the old metal reservoirs.
One problem with molded plastic radiator reservoirs and their plastic mouth assemblies has been related to the overflow tube nipple that projects outwardly from the tubular body of the mouth assembly and receives an end of the overflow hose. In plastic mouth assemblies, it is not uncommon for these overflow nipples to become brittle and to be broken-off during normal maintenance procedures on the engine. Once broken-off, the overflow tube nipple will not receive the end of the overflow hose in a sealing manner and coolant can leak from the system. In the past, when an overflow tube nipple was broken-off in this manner, the entire radiator reservoir and its mouth assembly had to be replaced since they are all molded as a unitary plastic element. Obviously, such replacement is time consuming and expensive and results in unexpected repair cost when an overflow tube nipple is accidentally broken-off.
Accordingly, there exists a need for a method of repairing the broken-off overflow tube nipple of a plastic radiator mouth assembly without the necessity of removing and replacing the entire radiator reservoir. It is to the provision of such a method and to a kit for performing the method that the present invention is primarily directed.
Briefly described, the present invention, in a preferred embodiment thereof, comprises a method of repairing the broken-off overflow tube nipple of a radiator mouth assembly without the necessity of replacing the entire radiator reservoir. The method is intended for repairing broken-off overflow tube nipples of plastic radiator assemblies; however, it may also be applied to radiator mouth assemblies made of metal or other materials. The method comprises the steps of preparing the broken-off end portion of the overflow tube nipple by removing a predetermined amount of the end portion until the resulting end of the nipple becomes substantially flat and smooth. In one embodiment, a sufficient amount of the nipple is removed so that the resulting flat smooth surface is substantially flush with the tubular body of the radiator mouth assembly. In another embodiment, a predetermined amount of the broken-off end portion of the nipple is removed so that the remaining stub of the nipple projects a predetermined distance from the body portion of the radiator mouth assembly.
Once the broken-off end portion of the overflow tube nipple has been prepared, the method includes the further step of installing a replacement overflow tube nipple in the prepared end portion for affecting the repair and for receiving the end of an overflow hose. In a first embodiment, this is accomplished by inserting a threaded annular boss through the prepared overflow tube nipple from the inside of the mouth assembly until the threaded portion of the boss protrudes from the assembly. A replacement overflow tube nipple is then threaded onto the protruding threaded portion of the boss. At least one gasket in the form of a rubber O-ring is positioned between the replacement overflow tube nipple and the prepared flat smooth end of the broken-off nipple and the replacement nipple is tightened against the gasket. This prevents leakage of coolant from the repaired area.
In a second embodiment, the prepared stub of the broken-off nipple is internally threaded with a tap and a replacement nipple having external threads is threaded into the tapped prepared nipple. The replacement nipple is provided with a shoulder and a gasket in the form of a rubber O-ring is positioned between the shoulder and the flat smooth prepared end of the broken-off nipple to prevent leaks from the prepared area.
In each case, the repair is completed quickly and easily and at a minimum of cost. When the replacement nipple has been attached to the radiator mouth assembly, the overflow hose is attached to the replacement nipple and the repair is complete.
Thus, it is an object of this invention to provide a method of repairing the broken-off overflow tube nipple of a radiator mouth assembly that is quick, easy, and economical to perform.
Another object of the invention is to provide a method of repairing the broken-off overflow tube nipple of a radiator mouth assembly that eliminates the need to replace the entire radiator reservoir and mouth assembly when the original overflow tube nipple is broken.
A further object of the invention is to provide a kit that can be used by automotive repair persons to repair the broken-off overflow tube nipple of a radiator mouth assembly quickly and easily when the nipple is accidentally broken-off.
An additional object of the invention is to provide a repair method for overflow tube nipples of radiator mouth assemblies that is so easy, efficient, and economical that additional and unexpected repair bills to customers can be avoided.
These and other objects, features, and advantages of the present invention will become more apparent upon review of the detail descriptions set forth below when taken in conjunction with the accompanying drawings, which are briefly described as follows.